DEAR AMY: My sister is a clinical psychologist. Recently I introduced her to a close friend of mine.

My friend hosted a gathering for Easter and invited us both. I could not make it, but my sister did.

I received a call from my friend afterward. She was very upset. Apparently my sister took it upon herself to give unsolicited advice to some of the partygoers that she had just met. She jumped in when a child had a meltdown, chastising the parent and reprimanding the grandmother, causing an angry response from the grandmother.

My sister then insulted another individual she just met by criticizing this person's method of counselling in her own practice. I was told that many at the party were shocked and insulted by her lack of tact and social graces.

My sister makes a habit of telling people how to conduct their lives and aggressively pushes her opinions onto others under the guise of "just trying to help." She has alienated many family members over the years, asking personal questions to those she just met (for instance, asking young people about their sexual practices and birth control methods and then giving advice that is not wanted).

She seems to be especially intolerant of small children and openly criticizes the parents in front of everyone (she doesn't have kids). When relationships with loved ones are not going her way, she breaks down and cries like she is being mistreated. She says, "That's just how I am. You need to change how you feel." What should I say (or do) to get through to her? She is very intelligent, but never admits any wrongdoing on her part. -- Upset Sister

DEAR SISTER: Your sister should know well through her professional training that people don't actually need to change the way they feel.

People do frequently need to change the way they act, however. Let's start with your sister. Drawing on her expertise with how to deal with children, she will be familiar with the concept of "natural consequences."

A natural consequence of her intolerant and aggressive behaviour is for people not to spend time with her. I assume your mutual friend will stop inviting her to events (and your friend, not you, should handle this). You are in a position to influence your sister by telling her, "I love and respect you, but your habit of leaping over boundaries and injecting your views is tough to take. I don't like it, and it is affecting our relationship."

You cannot change your sister. You can only encourage her to work on her own personal growth, perhaps in therapy. I'll pass along a quote I have taped to my computer: "Unsolicited advice is always self-serving."

DEAR AMY: Last weekend was the beautiful wedding of my oldest daughter and new son-in-law.

As we recover from the festivities it was noted there were several no-shows. I totally understand that life gets busy. When you RSVP in February for an April wedding, all intentions are to show up. Then life happens. This leaves the bride holding the doggie bag.

Catered meals for weddings are expensive. If 10 or 20 people don't show, this adds up. If the caterer has a heads-up even a week before the event, quantities and prices can be adjusted. As wedding season approaches could you remind your readers that their presence will be missed but we don't need the leftovers or expense. Send your regrets ahead of time. -- Happy MOB in Portland

DEAR MOB: Sometimes people feel they've done their job as a guest by responding to an invitation in a timely fashion. But you raise a very important point: When plans change, notify the hosts, giving them time to adjust their head count and seating plans.